The present invention relates to novel asymmetric radial polymers. More particularly, this invention relates to asymmetric radial polymers of conjugated dienes and/or vinyl aromatic hydrocarbons and acrylic monomers.
As is well known in the prior art, radial polymers comprise three or more arms extending outwardly from a nucleus. Asymmetric radial polymers contain arms of at least two different polymers, which polymers may vary as to chemical composition, structure and/or molecular weights. Asymmetric radial polymers having arms of different molecular weights are sometimes referred to as polymodal polymers. The asymmetric radial block copolymers which are known generally are comprised of arms that are formed of blocks of vinyl aromatic hydrocarbons and/or conjugated dienes.
The present invention provides a different kind of radial asymmetric block copolymer. The invention described herein is a radial block copolymer which contains arms which are formed from the monomers described above and arms formed from acrylic monomers. These polymers are desirable because they incorporate polar functionality which may enhance the usefulness of the polymers in compatibility with polar polymers, adhesion to polar surfaces, and solubility or dispersibility in aqueous/polar media. These polymers may then be useful in adhesives, impact modification of engineering thermoplastics, and as compatibilizers for blends of polar and non-polar polymers.